G-mail

Your question is confusing at the very least. What do you mean by "delete previous unsuccessful attempts"??? If your attempts were unsuccessful, there's  nothing to delete. If however you do have an account, you can recover it as follows:

Forgotten username:

    1. Click I cannot access my account on the login page.
    2. Click I've forgotten my username.
    3. Enter your recovery email address in the Email field.
    4. Click Submit.
    5. Type the letters in the distorted picture in the appropriate field.
    6. Click Submit.   

A list of any usernames associated with that recovery email address will be sent to the address you provided.

Problematic password:

    1. Visit the password recovery page.
    2. Enter your username.
    3. Click Submit.

Once you've recovered your account:

Google currently offers no means of closing your Gmail account while leaving your Google account open. You have 2 options, both from the Settings submenu accessible from the gearwheel icon at the upper right. From Settings go to Accounts and Imports.

Option 1: Just change your Gmail address to one that no one will use. Edit the "Send Mail as:" information.

Option 2: Close your Google account. From "Change account settings:" go to Other Google Account Settings. Then under Services look for "Delete entire Google account," and proceed.

(The above applies to Gmail's standard view. The interface for Basic HTML view is somewhat different.)

 

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